Unexpected behaviour on list of environment variables.

So the issue when I trie to provide multiple env vars
```
environment: ENVIRONMENT=production,AWS_WHITE_LIST=foo.bar,jenkins,bar.baz,baz.foo,DB_NAME=sfasfsf,DB_USERNAME=asdasdasd,SLACK_CHANNEL_ID=QWERTY
```
On providing `AWS_WHITE_LIST` it will read only to `foo.bar` first element, and then it stops and will go to next env var. Escaping. quoting won't work here.

Use the environment example in the issue as the reproduction and trace how the action parses the `environment` input. Verify how comma-containing `AWS_WHITE_LIST` values are separated from later variables, then confirm the full example is handled without truncating that value.

Written by the indexing model from the issue text.